Indices such as the Gini coefficient have been used to measure the spatially uneven distribution of crime in cities. However, the Gini coefficient has the disadvantage of overestimating spatially uneven distribution of crimes under low crime frequency situations, including Japan. To overcome this problem, this paper analyzes the spatially uneven distributions of eight types of crimes reported in the last 12 years in the 23 wards of Tokyo and Osaka City using the “Rare Event Concentration Coefficient” (RECC). The results of the analysis were as follows: a) RECC was able to detect spatially uneven distributions in low-frequency crime situations, which is difficult to detect with the Gini coefficient; b) RECCs were large for commercial and office burglaries, and small for residential burglaries, thefts from car, vehicle thefts, bicycle thefts, and purse snatchings.